Synthesis of Imidazole-2,3-dihydrothiazole Compounds as VEGFR-2 Inhibitors and Their Support with in Silico Studies

In this study, 12 novel 2-((1-(4-(1H-imidazol-1-yl)phenyl)ethylidene)hydrazineylidene)-3-ethyl-4-(substitutephenyl)-2,3-dihydrothiazole derivatives were obtained. Among these compounds, 2-((1-(4-(1H-imidazol-1-yl)phenyl)ethylidene)hydrazineylidene)-4-([1,1′-biphenyl]-4-yl)-3-ethyl-2,3-dihydrothiazole ( 4h ) was chosen as the most active derivative in the series. According to the MTT results, compounds 4h and 4k showed activity with IC₅₀=4.566±0.246 μM and IC₅₀=4.537±0.463 μM, respectively. Unlike other derivatives, compound 4h carries a phenyl ring in the 4th position of the phenyl ring. This bulky group allowed the compound to settle in the enzyme active site. Dynamic studies show that the stability of the compound does not change over 40 ns. RMSD, RMSF and Rg parameters all remained within acceptable limits. The uninterrupted aromatic hydrogen bonding of the enzyme active site with the important amino acids Cys919, Glu885 and Asp1046 proves the inhibitory potential of compound 4h on the VEGFR-2 enzyme. It is thought that more active compounds will be reached with the derivatives to be synthesized starting from compound 4h .     

Isolation and Characterization of a Bacteriocin-Like Substance Produced by <Emphasis Type="Italic">Geobacillus toebii</Emphasis> Strain HBB-247

A total of 201 thermophilic bacteria isolated from various thermal spring, mud and soil were tested for their antibacterial activity. Among the mostly active isolates, Geobacillus toebii HBB-247 was further examined. Bacteriocin-like inhibitory substance (BLIS) produced by strain HBB-247 was found to be stable up to 60°C, sensitive to proteolytic enzymes and effective against Enterococcus faecalis, Listeria sp., E. avium, Clostridium pasteurianum, Cellulomonas fimi and some thermophilic strains isolated and identified in this study. As a result of Tricine-SDS-PAGE molecular weight of BLIS was estimated about 38 kDa. Production studies showed that G. toebii HBB-247 starts to produce antibacterial substance at early logarithmic phase of growth and maximum production was detected at the end of the logarithmic phase.